Competitive Programming Setup

A powerful, automated toolkit for competitive programming that streamlines your workflow from problem fetching to testing. Built with Python and C++, this setup handles everything so you can focus on solving problems.

Features

One-Command Problem Setup

• Automatically fetch sample test cases from Codeforces
• Parse time limits and metadata
• Ready-to-test environment in seconds

Lightning-Fast Testing

• Parallel test execution with custom timeouts
• Detailed diff output for wrong answers
• Color-coded results (PASSED, FAILED, TLE)
• Smart executable detection (Windows/Linux compatible)

Advanced Debugging

• Comprehensive debug template with colored output
• Variable inspection with type-aware printing
• Performance timing for code sections
• Support for complex STL containers

Cross-Platform Build System

• Optimized compilation flags (-O3, -std=c++2b)
• Debug builds with full error checking
• Automatic dependency management
• Windows and Linux compatible

📁 File Overview

File	Purpose	Key Features
MakeFile	Build automation & workflow management	Cross-platform, contest fetching, testing pipeline
cf_fetch.py	Codeforces sample test downloader	Auto-detection, HTML parsing, metadata extraction
run_tests.py	Test runner with advanced verification	Timeout handling, detailed diffs, color output
debug.cpp	Advanced debugging template	STL container printing, timers, colored output
cpp.json	VS Code Snippet	Instant template generation with timestamp & debug setup

Quick Start

Most Common Commands (on windows)

# Fetch problem and run tests (most used!)
make -f makefile test CONTEST=1789 PROBLEM=C

# For gym contests
make -f makefile test GYM=104114 PROBLEM=A

# Test existing downloaded samples
make -f makefile test-only PROBLEM=B

# Compile and run with input.txt
make -f makefile run

# Debug build with full error checking
make -f makefile debug

Powerful Features in Action

1. VS Code Snippets

This setup includes a custom VS Code snippet (cpp.json) that instantly generates your competitive programming template with the current timestamp and debug configurations. (and also any other templates you would like to add).

Installation

To make the snippet work, you must place the cpp.json file in your VS Code User Snippets directory:

Required Path:

C:\Users\(username)\AppData\Roaming\Code\User\snippets

2. Intelligent Problem Fetching

make -f makefile fetch CONTEST=2139 PROBLEM=B

What happens:

• 🌐 Fetches from https://codeforces.com/contest/2139/problem/B
• 📊 Parses HTML to extract sample inputs/outputs
• ⏱️ Extracts time limit (e.g., "2 seconds")
• 📝 Creates tests/B1.in, tests/B1.out, tests/B_metadata.json

3. Advanced Test Runner

make -f makefile test-only PROBLEM=B

Output Example:

🔵 Using time limit: 2.0 seconds (from tests/B_metadata.json)
🟡 Running tests for problem B...

✅ B1: ACCEPTED
✅ B2: ACCEPTED  
❌ B3: WRONG ANSWER
   Expected:
     1: 42
     2: 13
   Got:
     1: 41
     2: 13
   Differences:
     Line 1: Expected '42', Got '41'

✅ 2 / 3 tests passed ❌

4. Powerful Debug Template

This debug template is mainly by: Anshul_Johri, you can find the full blog on codeforces here and was modified by me to add LabeledTimer

Include debug.cpp in your solution:

#ifndef ONLINE_JUDGE
#include "debug.cpp"
#define TIME_BLOCK(name)    \
	if (bool _once = false) \
	{                       \
	}                       \
	else                    \
		for (__DEBUG_UTIL__::LabeledTimer _t(name); !_once; _once = true)
#else
#define debug(...)
#define debugArr(...)
#define TIME_BLOCK(name) if (true)
#endif // Debugging locally

Example:

vector<int> arr{1, 2, 3};
map<string, int> mp;
mp["hello"] = 5;
mp["world"] = 3;
debug(arr, mp);

Debug Output:

🔵 42: [arr = {1,2,3} || mp = {("hello",5),("world",3)}]

Performance Testing

TIME_BLOCK ("sorting")
{
    sort(arr.begin(), arr.end());
}
// Timers print automatically when destroyed

Output:

🔴 [TIMER] sorting took: 0.000123 s

5. Smart Cross-Platform Compatibility

• Windows: Auto-adds .exe extension, handles Windows paths
• Linux: Native Unix commands and paths
• Both: Color support detection, proper encoding handling

Typical Workflow

# 1. Write your solution in Code.cpp
# 2. Fetch and Test
make -f makefile test CONTEST=1847 PROBLEM=D

# 3. For subsequences testing (no need to fetch again)
make -f makefile test-only PROBLEM=D

# 5. Submit when all tests pass!

Custom Test Cases

Add your own test cases:

# Add tests/D4.in and tests/D4.out
make test-only PROBLEM=D  # Will run all tests including custom ones

Why This Setup Rocks

Speed:

• Fetch and test a problem in under 5 seconds
• No manual copy-pasting of test cases
• Instant feedback with detailed error analysis

Accuracy:

• Exact time limit enforcement from problem metadata
• Precise output comparison with whitespace handling
• Catches edge cases other setups miss

Flexibility:

• Works with any Codeforces contest (contest/gym/problemset)
• Supports custom test cases
• Cross-platform compatibility

Productivity:

• Focus on algorithm, not setup
• Visual debugging with colored output
• Automated build optimization

Setup Requirements

# Required tools
g++          # C++ compiler with C++2b support
python3      # Python 3.6+

# Optional but recommended  
make         # For using the Makefile commands

📊 Success Stats

With this setup, you can:

• ✅ Fetch and test a problem: < 10 seconds
• ✅ Debug complex data structures: Visual colored output
• ✅ Handle 100+ test cases: Automated with timeouts
• ✅ Work on any platform: Windows/Linux/Mac compatible

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"Competitive programming is about solving problems, not fighting tools. This setup gets you there faster."